A generic insertion head comprises a cannula housing in the form of an application part that is applied on the skin, whereby the application part has a piercing device—in the form of a needle—and a flexible introducing device—in the form of a flexible cannula—for an active substance. The piercing device supports the flexible introducing device during the penetration into the skin and it is subsequently drawn out of the flexible introducing device through a septum so that the active substance can be administered through the flexible introducing device in and/or under the skin. The septum is located above the flexible introducing device and it closes the application part after the drawing out of the piercing device at the location at which the latter was previously located.
Such known application parts were previously almost always produced in such a manner that in the first manufacturing step a stabilizing pin is introduced into a flexible cannula in order to be able to better work the flexible cannula during the manufacturing of an associated cannula housing. The structural unit prepared in this manner is then introduced into a previously manufactured cannula housing in order to be able to connect the flexible cannula and the cannula housing to one another by a thermal process in a stable manner. Subsequently, the stabilizing pin is drawn out of the flexible cannula and replaced by the actual piercing means. Damage often occurs to the flexible cannula during the insertion of the piercing means into the flexible cannula of the cannula housing, which unfortunately has the consequence of relatively high rejection rates.
The problem of improving the manufacture and the service life of a generic cannula housing remains a desire.